| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inverter in which a ripple current can be prevented from increasing in response to the switching timing of a triangular reference wave without complicating the overall control even when two triangular reference waves having phase difference of 180° are used in two-phase modulation system. <P>SOLUTION: Each phase current of a three-phase motor 42 is read in, output voltage pattern of each phase of the three-phase motor 42 is estimated on the basis of each phase current, output voltage pattern of each phase is divided every 30° on the same phase axis to obtain twelve equal areas, output voltage pattern of each phase of the three-phase motor 42 is determined for each area, a switching signal is obtained for each area, and the output voltage pattern of each phase is compared with triangular reference waves A and B thus outputting drive signals D1-D6. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
